Electric riveting-tool.



L. HIRSH1 ELECTRIC RIVETING TOOL.

APPLICATION FILED JULY 31.1916.

1,251,665. Patented. Jan. 1, 1918.

2 SHEETS-SHEET 1.

I 0 H Wab- L; HIRSH.

ELECTRIC RIVETING TOOL APPLlCATlON FILED JULY 3!. i916.

Patented Jan.1,1918.

2 SHEETSSHEET 2- To all whom it may concern.-

nno nmsn, or

raaan FICE.

oornn, rarssounr, nssrenon or ONE-HALF TO ROBERT JAMES or orrtnnroornn, iurssouar.

ELECTI-EIQ BIVETTEN (El-T0011.

menses.

of itetters Itatcnt.

Patented Jan. 1, 1918.

Be itknown that I, LEO HIRsH, a citizen of the United States, residing at Chillicothe, inv the county of Livingston and State of Missouri, have inventedcertain new and useful Improvements in lectric Rivetin Tools, of which the following is a speci cation.

My invention relates to new and useful improvements in electrically operated riveting tools, the primary object of my invention being the provision of a riveting tool including an -impact receiving rivetinghead operated by a plunger which in turn is operated by cooperating solenoid coils, the plunger in cluding a core common to'both solenoids.

A still further object of my invention consists in providing bearings for the plunger which serve to centralize the core, diametrically, with respect to the coils which are located in longitudinal alinement with each other within the body of the tool.

A still further object of my invention consists in the provision of an improved circuit controlling device which governs the alternate closing of circuits through the coils, this device being actuated and controlled by the movement of the plunger itself in such a manner that no springs are necessary, one coil being energized just prior to the completion of the stroke of the plunger away from such coil, due to the previous energization of the other so that the magnetic forces of the coils themselves serve as buffers'for cushioning the action of the plunger.

A still further object of my invention is to provide the tool with a-convenient form of.

handle by means of which it may be held in engagement with a rivet being operated upon and with a switch convemently dlsposed with respect to the handle for controlling the supply of current to the tool.

With these and other objects in view, my

, invention will be more fully described, illustrated in the accompanying drawings, and thenspecifically pointed out in the claims which are attached'to and form apart ,of

i this application.

In the drawings Figure 1 is a perspective view of my im- 1 proved riveting tool Fig 2 is a central longitudinal section taken through the casing, showing the 0011s and circuit controller in elevation;

Fig. 3 is a sectional view taken at right angles to Fig. 2, showing the coils and their spool also in section;

Fig.4 is an enlarged fragmentary sectional view of a portion of the structure shown in Fig. 3, showing portions of the circuit controller in section;

Fig. 5 is a transverse section'taken on the line 5--5 of Fig. 4,1ooking in the direction of the arrows; i

Fig. 6 is a diagrammatic view, showing the method of wiring the tool.

Corresponding and like parts are referred to in the following description and indicated in all the views of the drawings by'the same reference characters. 1

Although my improved tool is intended primarily as a riveting tool, it will be understood that the same tool may be employed within this casing and adjacent one end thereof is'a compound spool 11 for the windings of solenoid coils 12 and 13 which are preferably of equal size and strength. This spool includes a tubular body portion having terminal flanges 14 and an intermediate parting flange 15 which hold the windings of the coils upon the body of the spool and in spaced relation to each other, these flanges being of such diameter as to fit snugly within the casing and centralize the sleeve of the spool with respect to the casing. .An internal collar 16 closes one end of the casing, being secured preferably to the flange 14 of the spool and also to the casing and is formed with a central opening to receive a metallic sleeve 17, the inner end of which seats in a circular recess 18 formed in the outer end of the spool and the internal diameter of which is preferably somewhat less than the internaldiameter of the tubular body of the spool 11.

Reciprocally mounted in the free end of this sleeve 17 1s the impact receiving head 19 in the form of a cylindrical body fitt ng loosely in the sleeve and having a reduced inner terminal 20. The outer end of the body is enlarged to provide a riveting head 21 formed in its outer face with a concavity 22 to insure proper engagement with and heading over of the rivet. A cylindrical core 25, common to both the solenoids 12 and 13, is mounted within the spool 11, being of somewhat less diameter than the internal diameter of the spool, and at its ends carries the extension forming rods 26 and 27 which are fixed to the ends of the core to extend in alinement therewith. The core is preferably formed of soft iron and the extensions 26 and 27 of brass, the extension 26 fitting within the sleeve 17 which forms a bearing for it, whereby it may centralize the core with respect to its spool 11. In like manner, the opposite end of the spool is formed with a. recess 28 to seat a bearing sleeve of brass or other suitable material 29 which forms a bearing for the extension 27 of the core 25. A centralizing collar or ring 30, preferably formed of fiber or other insulating material,

supports the free end of the bearing sleeve 29 and also serves as a support for the switch mechanism, as will be explained.

This collar 30, at one side, is formed with a recess 31 to receive one end of a switch bracket 32 in the form of a metal bar having spaced parallel arms 33 and 34, the former being relatively short and engaging against the outer face of the collar 30 and the latter extending to a point substantially central of the casing 10. These arms, in spaced relation to the body of the bracket 32, are formedwith alined bores 35 to receive the reciprocating member 36 of the switch. This member includes a cylindrical contact rod 37 carrying spaced collars 38 and 39 which are preferably adjustably.

mounted upon the rod by set screws 40. The ends of the rod 37, exteriorly of the collars, are reduced to form sleeves 41 and 42 of insulating material, such as fiber, which are in turn held in place by brass sleeves 43 fixed upon the ends of the rod. By this arrangement, the entire rod 37, save for the stop collars, is of uniform diameter throughout its length. The inner end of the extension 27 of the core or plunger of the tool is provided with a collar 44 of fiber or other insulating material so proportioned that during reciprocation of the plunger it will alternately engage the stop collars 38 and 39 of the reciprocating member 36 of the commutator to move the latter back and forth. Seated in recesses formed through the body of the bracket 32, adjacent its arms 33 and 34, are tubular plugs 45, of fiber or other insulating material, in which are mounted brushes 46 and 47 which constantly engage either the fiber sleeves 41 and 42 or the metallic sleeves 43 of the reciprocating member 36, being held in such engagement by helical springs 43 bearing against the outer ends of the brushes and secured in the plugs by screws 49 which also serve as binding posts for connecting the current carrying wires, as will be later apparent. It should be noted that the spacing of the insulating sleeves of the reciprocating member 36, relative to the spacing of the brushes 46 and 47' is such that when one brush engages one of the insulating sleeves, the other brush engages one of the metallic sleeves which, as it is in electrical connection with the rod 36, is consequently in electrical connection with thebracket 32 through which the rod reciprocates.-

That end of the casing 10, adjacent the switch is closed by a disk or plug 50, of fiber or other suitable insulating material, and is provided exteriorly with a substantially U-shaped handle 51 by means ofwhich the tool be properly manipulated. A finger controlled switch lever 52 ispivoted intermediate its length upon a bracket 53 mounted exteriorly of the disk 50 and in the same plane with the handle 51 and its inner end is pivoted to a plunger 54 reciprocally mounted through the central portion of the disk 50. This inner end of the plunger 54 is threaded to receive a contact carrying head 55, of fiber or other insulating material, having a reduced externally threaded extension to seat in the threaded socket of a tapered ing post for connection with one of the wires of the circuit controlling the tool. Thiscontact head 56 may, upon proper swinging of the lever 52, be forced between the peripherally disposed resilient contact'fingers 58 of a socket shaped contact member 59 which is secured to the arm 34 of the bracket 32 by a clamping screw 60. 1

My improving riveting tool is intended to be operated by an alternating current, such as is commonly supplied in most cities for electric lighting purposes and its coils are, therefore, wound for such current. Obviously, however, they may be wound for any current desired. Wires 61 and 62, suitably insulated, lead from one member of a plug and socket connection, not shown,

through the disk or closure 50 of the tool. The wire 61, within the casing of the tool, is connected to the contact 56 by the screw 57, while the -wire 62 is connected by formed by the contact members 56 and 59 in open position .so that no current will be supplied to either coil, this spring engaging a shoulder formed on the plunger 54:.

From the foregoing description, taken in connection with the drawings, the operation of my improved riveting toolwill be readily understood. Assuming that the wires 61 and 62are connected to any suitable source of electrical current and that the tool is held -with its riveting "head 19 in engagement with a rivet to be headed, will be clear that-closing of the switch by swinging the fingerlever' 52 will close a circuit through the tool. Assuming-that the .tool is in the position shown in Figs. 3 and 4 of the drawings, that is with the plunger and riveting head in' retracted position, it will be clear that current will pass from the switch through thebracket 32 to the rod 37 and-so to the brush 46, the brush 47, at this time engaging the insulating sleeve &2. From the brush 46, the current will'pass through the-wire to the solenoid winding 12 and from this winding through the wires 63 and 62 back to the line. This energiz'ation of the coil 12 will act to draw the core '25 to a central position with respect to the coil 12, with the result that the impact or operating plunger of the tool willbe driven into engagement with the riveting head 19 to eX-- tend this head and impart a blow to the rivet beingoperated upon. This movement of the plunger, however, causes its collar l l to engage the collar 38 of the reciprocating member 36 of the switch and pick up this reciprocating member in such a manner that before the movement of the plunger has been completed, the brush 46 will be in. engagement with the insulating sleeve 41, instead of with the rod 37, while the brush 4L7 will no longer engage thesleeve 42, but will engage the rod 37. 'Because ofthis, the current will be cut out from the coil 12 and instead will pass from the brush 47 through the wire 63, coil 13 and wires 64 and. 62, energizing the-coil 13 and causing a reverse movement of the .core 25 and its extensions forming the impact plunger of the tool. It will, therefore, be clear that as long as the manually controlled switch is closed, a constant and rapid reciprocation of the impact plunger is assured. No springs for limiting or Icushioning the movement of the impact plunger, which would naturally also limit its effectiveness, are necessary as the \mag- 'netic'force of the coils themselves, operating upon a common plunger, serves to cushion the movement of the plunger and act as a buffer for it. The bearlngs for the extensions of the core insure a proper'centraliz'ation of the core with respect to the windclaims.

ings of the solenoid coils so that the 'coils may exert the greatest possible forceupon the core proper.

Obviously, various changes in details of construction and arrangement of parts may K be made and I do not, therefore, limit myself to the specific details shown and described but reserve the right to make any changes within the scope of the appended Having thus describedl the invention, what is claimed as new is: a

1. An impact tool including a substantially cylindricalcasing, a double spool of insulatingmaterial disposed within the casing and including a tubular body and spaced annular flanges, the flan ges engaging. the inner Wall of the casing. to centralize the body, solenoid windings one on each part of the spool with their other convolutions within the circumferences of the flanges and consequently out of engagement with the casing, -metallic bushings, engaging in the ends of the spool and of less internal diameter than the internal diameter of the body, a plunger reciprocally mounted in and journaled by the bushings whereby the bushings hold them in spaced relation to the body, and means operable by reciprocation of the plunger for alternately opening a circuit through one solenoid winding and closing it through the'other.

2. In an apparatus of the class described, the combination with a pair of circuits and a reciprocating member carrying an abutment, of a bracket forming a portion of both circuits, a pair of brushes carried by and insulated from the bracket and each forming a portion of one-of the circuits, 2.

contact member reciprocally mounted in the bracket, spaced collars adjustably mounted collars carried by the contact member and adjustable toward and away from each other and contact brushes carried by the bracket and insulated therefrom,'the contact brushes alternately engaging the contact member or an insulated sleeve thereof during reciprocation of the contact member.

i In testimony whereof I affix my signature.'

LEO HIRSH, Ii-8. 

